Hello! With a fresh .htaaccess, Piwik works fine, but OctoberCMS shuts down and stops loading. But when I use the OctoberCMS .htaccess, Piwik stops working.

Any idea?

Interesting. I have not encountered this before. In theory Piwik should not be affected by the .htaccess values in your OctoberCMS installation. When you say it stops working, what do you mean exactly? Is the connection refused?